Not only that, but the Confederate constitution had a clause that disallowed any Confederate state to abolish slavery. So much for the "States' Rights" argument.
Actually, both Jeff Davis and the Declarations of Causes issued by the Confederate states said plainly that they were seceding in order to defend slavery and white supremacy. The only "heritage" the Confederate flag stands for is the heritage of slavery and racism. To claim otherwise is to either lie in one's teeth or to display a complete ignorance of history.